Pedestrian detection is a key problem in a number of real-world applications including auto-driving systems and surveillance systems, and is required to have both high classification and localization accuracy. Driven by the success of general object detection, many of the proposed pedestrian detectors [1]}, [2]}, [3]}, [4]} still follow the basic practice such as Faster R-CNN [5]} and SSD [6]}. Therefore, Intersection over Union (IoU), which is required to assign proposals, has been one indispensable metric in the recent frameworks.
